SQL MCP Server

Governed SQL gateway MCP server that lets an assistant query PostgreSQL, MySQL and OceanBase through controlled tools, policies and cost limits instead of…

What you can do

• Query PostgreSQL, MySQL and OceanBase through explicit entities and whitelisted relational-algebra operations rather than free-form SQL
• Enforce field and row governance, including RBAC, column ACLs, row policies and masking, on every access
• Apply cost controls such as EXPLAIN pre-screening, result caps, timeouts and session or tenant budgets
• Isolate tenants and fail closed when a safety property cannot be proven
• Optionally expose a separate execute_sql escape hatch, off by default and only for explicitly granted users
• Run with audit logging, config hot reload and OpenTelemetry hooks

When to use it

Use it when an assistant needs database access but the operator wants deterministic, policy-bound queries instead of raw SQL, for example multi-tenant or regulated data where field masking, row policies and cost limits matter.

Requirements

Runs locally over stdio, typically via the published Docker image or a Go 1.26.10+ source build. Needs a supported database (PostgreSQL, MySQL or OceanBase) and a database DSN supplied through the DATABASE_DSN environment variable, plus a YAML configuration file. Docker Compose is suggested for the quickstart.